Electromagnetic bandwidth for communications is a limited and some times very costly resource. For example, auctions of licensed spectrum have garnered the equivalent of billions of dollars for various governments, including that of the United States of America. Given the considerable expense that companies such as wireless voice communications companies must bear to acquire the right to use a valuable portion of the electromagnetic spectrum, there is considerable emphasis on efficiently using that spectrum from an economic perspective both to justify the purchase of spectrum and to create and/or perpetuate a profitable enterprise. One approach to maximizing the economic efficiency of a portion of licensed spectrum is to permit the maximum number of paying customers to use that spectrum as possible. In digitized voice communications, this can mean packing as many simultaneous conversations into the spectrum as possible, while maintaining the quality of the communications.
Maximizing the efficient use of electromagnetic spectrum for communications faces a number of obstacles. The electromagnetic spectrum, even licensed electromagnetic spectrum, is unfortunately susceptible to electromagnetic noise that affects the quality of the communication signals being transmitted through it. Correspondingly, although communication signals can be modulated onto one or more carriers with frequencies within the licensed spectrum by a variety of different modulation schemes, in general, the more efficient the modulation scheme is at squeezing information onto the carriers, the more susceptible that scheme is to the effects of noise which affect the quality of the underlying communications. Accordingly, it would be desirable to have a system and method for mitigating these problems in order to more efficiently use the available electromagnetic spectrum.
In the drawings, the same reference numbers identify identical or substantially similar elements or acts. To easily identify the discussion of any particular element or act, the most significant digit or digits in a reference number refer to the Figure number in which that element is first introduced, e.g., element 102 is first introduced and discussed with respect to FIG. 1.
Note that the headings provided herein are for convenience and do not necessarily affect the scope or interpretation of the invention.